In the General Industry standard for Air Contaminants found in 29CFR 1910.1000, employers are tasked with maintaining employee exposures below the Permissible Exposure Limits (PELs) listed in Tables Z-1, Z-2 and Z-3. Although there is no specific requirement to conduct air monitoring; employers must ensure that employees are not exposed to airborne concentrations in excess of the PEL. It is wise to collect air samples for those substances most likely to produce significant employee exposures to verify exposures are below established PELs.

In the vertical standards, or substance specific standards found in Subpart Z 1910.1001 and above, there are some specific requirements to conduct initial air sampling for those regulated substances when exposures are likely to exceed the Action Level (usually set at 1/2 the PEL). A negative initial determination usually requires no further air monitoring unless changes are made that could increase employee exposures above the Action Level.

If initial monitoring indicates employee exposures above the Action Level but less than the PEL, additional monitoring is usually required at some frequency (typically at least every 6-months).

If air monitoring indicates employee exposures are in excess of the PEL, periodic monitoring is required at least quarterly in most instances.

After monitoring indicates elevated employee exposures in excess of the Action Level or PEL, additional monitoring should continue at the frequency specified (quarterly or semi-annually) until such time as two consecutive measurements, taken at least 7-days apart, indicate exposures at a lower exposure level.

For specific substance monitoring requirements, the specific standard should be consulted.

If you need assistance with air monitoring, please contact me for a free, confidential discussion concerning your needs!